Valve tappet



' Patented Jan. 3, 1922 E WA J. A. GERMONPREZ.

vwww TAPPEI.

` APPUCATON FILED JAN. 3, IQZI.

a citizen o'f the United-A States of America, re-

and ate of Michigan, have invented certain `new and useful mprovements in Valve Tappets, of which the following visa specification, reference being had therein to the' ac-Y companying drawings. l

Gas and other internal combustion engines as commonly constructed havelvalves which are operated in timed relation to the engine pistons by means of vcams upon a cam shaft which cams engage valve tappets and h ft the'valves in operating the saine. The rapid rotation of the cam shaft and the .constant hammering action vof the cams against the tappet`heads, soon wears the heads and causes lost motion.A The heads of the tappets are 'therefore usually hardened, but to\.

harden the heads of the tappets tothe desired degreebf hardness is a very difficult v operation and-often results in the metal be- Y iiigtoo hard and brittle so that the heads 25 l break in operation.

The object of this invention is to provide a hard wear surface for the heads of tappets to be engaged by the' cams and further-to provide such wear surface in the form of a hardened steel disk. lt is also an object -of the invention to provide means for securing the disk to the headA in such a manner that the disk will always .be firmly seated and cannot become detached or loose in operation. v r

fWith the above'and other. ends in view, the invention consists in the-matters hereinafter/set forthfand more particularly pointed out/in they appended claims, reference b e- .ing had to the accompanying drawing, in which-v Fig. 1 is a side elevation of a tappet wit the headthereof shown in section;

Fig. 2 is an elevation ofthe lower end face of the tappet shown in Fig. 1; f

Fig. 3 is a sectionaldetail illustrating the manner in which a facevdisk-is appliedto -the tappen head;and l v Fig. 4 is an end elevation of agas engine lwith parts broken away and in section to show a tappet in place thereon and cooperating engine parts.

- As shownin Fig. 21, 1 indicates the usual engine cylinder, 2 the' crank-case, 3 a cam shaft within'the case havingacamlthereon 'to engage the head of a tappet 6 which'i's aan stares siding at Detroit, inthe county-0f VVa'yne Parana-oriana.

or nn'rnorr, nicnas/aai.

narran i Specicationof Letters Patent. I `Patq5m$d am, 3, 119220:..

3, 1.921. Serial No. 434,487,

mounted to slide within a suitable bearing member 7- on the crank case ofthe engine. 8 indicates the usualvalve stem and 9 the 'usual adjustment between the lower end of the stem and the upper'end ofthetappet V6,5

and 10 indicates the us al coiled spring sleeved over the valve stem between a suitable abutment 1l on the stem and the engine casing.

. .The tappet indicated as a whole at 6, edmprises -a cylindrical body 12 which engages and slides within the bearing 7 on the engine crank c ase and this body'l2 is formed Y .at its lower end with a circular head 18 of considerably greater diameter than the diameter of the body. This head is recessed in its lower end face, ange 15 surrounds this recess. The bottom 16 of the recess is curved transversely of the ongitudinal-a-Xis of the head and s tem- 12so that at the axis or center -of the recess 14 this bottom wall is higher than at any other point of its surface,

upwardly in a direction from this axis toward the flange 15. ,y .v

To form a hardened surface for' the head as at 14, and any edge" thus curving outwardly andV 13 of the tappet, a disk17 is formed of steel l l or other suitable material which is properly hardened and ground to give avery smooth, Ahard lower surface. The edge of this disk iss-formed' at an incline, as shown at 18, providing an edge portion at the upper side of the disk which is of greater vdiameter than the lower surface ofthe disk. The disk 17 is secured in place within the #recess 14, by forcing it against the bottom wall of the recess under heavy pressure, thus springing or flexing the disk into conformity with the curved bottom of the recess and into close contact therewith and while so held in contact, the edge flange 15 on the head 13 isv formed ovenand Adown `upon the inclined edge 18 of the disk, thus 'securely locking the disk within the recess of the head. rlhe diskl head in use but will always-remain firmly Y held in place by this spring action of the disk itself.Y lf it were not for this tendency of the disk to spring back to its flatcondition, it wouldvery soon become loose within the recess of the head and would then wear and finally drop out.

By this construction a very light, hard, smooth surface is provided for tappet heads to take the wear of the cams and this surface is a separate part whichis applied to the head in sucha manner' as to'obviate any danger of itsbcoming loose or detached in use. By "providing the separate disk facing, the bouy or stem l2 and head portion 13 of the tappet may be formed from any suitable steel or other material which may be easily machined and then the hardened steel disk applied thereto. The disk may be given the .proper hardness without danger of making.

it brittle and the manufacture of the tappet is greatly facilitated by yconstructing the body separate from the face so that the body may be made of material which may be read ily machined.

Having thus fullyl described my invention, what I claim is 1.` As a new .article ofmanufacture, a tappet comprising a body having an end por.- tion formed with a surface which is curved transversely of the longitudinal axis of the body, and a resilient cam engaging element held in close contact with said curved surface throughout its area by the yielding enportion of thebody.

3. As a new article of manufacture, a tappet comprising a body having-an end portion formed with a surface curved transversely of the longitudinal axis of the body, a resilient cam engaging disk seated upon said surface* and sprung laterally into firm contact therewith throughout said surface,

and means engaging the edge portion of said disk to hold said disk in its sprung condition.

f 4:. As anarticle of manufacture, a-tappet comprising a body having an end portion formed with a recess in its end face with the bottom of the recess curved transversely of 4the longitudinal axis of the body and an 4edge fiange surrounding the recess, and adisk within the recess in close contact with its bottom throughout the area thereof and held in-such contact by theyielding engagement of the edge portion of the disk with said fiange.

As a new article of manufacture, a tappet' comprising a body having a head formed with a recess in its end face, said re.

A pet.

head formed with aV smooth outwardly cess having a bottom curved transversely of the head, said head being formed with an edge fiange surrounding said recess, and. a disk forced into contact with the curved bottom of the recess and sprung laterally thereby, said "disk being held' within the recess by the yielding engagement of its edge portion with said fiange. I .Y

6 As a new article of manufacture, a

valve tappet wherein a solid unyielding body is providedv with an outwardly curved end surface of smooth unbroken area and a separate hardened member is secured under stress in firm contact throughout its areaY with said end surfaceto provide a hardened unyielding contact end surface for the tap.

' 7. As a new article of manufacture, a `valve' tappetcomprising a body having' al curved'end surface, a hardened disk, and means forsecurmg said'disk with one face in firm contact with said surface throughout its entire area;4 v

8. As new article of manufacture, a valve tappet comprising an unyielding body having a head formed with a smooth end surface of unbroken'area, a thin disk forming a hardened Contact covering for said end surfacev of the4 head, and means for holding one face of said 'disk infirm contact with said end surface of the head throughout the areaof said face,'one of said contacting surfaces being curved. r

9. As a new article of manufacture, a 100 valve tappet comprisin a cylindrical body having a head portion ormed with a recess in its end, the bottom of which recess is continuous 'and unbroken throughout its area,

and a hardened disk held in said recess with 105.

one face in firm contact throughout its' area withvsaid bottom of the recess,yby the por# tion of the head surrounding the recess, one of said contacting surfaces being curved.

10. As a new article of manufacture, a 110i valvetappet'comprising abodyhaving a head portion formed with a smooth end sur-- face, a hardened' disk,- and means forsecurirrg saiddisk flexed with one face in firm contact with said surface throughout its en@ '115 tire'area. y 11,; Asa new article'of'manufacture, ya valve tappet comprisin acylindrical 'body having a-head portion formed with 'a yrecess in its end, the bottom'of whichrecess is.120

continuous "and unbroken throughout its area, and a hardened disk held flexed in said recess with one face in firm contact through-l out its area with thebottom ofsaid recess by the portion of the vhead surrounding the recess. l s.

12. As a new article of fmanufacture, a valve tappet comprising a body'having a head portion formed with a smooth end surface at its laxial portion, a' hardened disk, 130

- and means-:for securing said disk flexed with" 'and a hardened disk firm contact with the bottom of said recess by the portion of the head surrounding the recess.

14C. As a new article oflmanufacture, a Valve tappet .comprlsing a body having a 15 head portion forming a seat, and a Har'dened flexed disk seated on said seat Vand held in irm contacttherewith by the resiliency of the flexed disk.

In testimony whereof I aix my signature 20 in presence of two witnesses.

JOHN n. GERMONPREZ.

Witnesses: I i 1 ANNA'M. DoRR, Linwrs E. FLANDERS. 

